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1.
Biomacromolecules ; 22(9): 3649-3667, 2021 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-34415743

RESUMEN

Cyclic polymers have long been reported in the literature, but their development has often been stunted by synthetic difficulties such as the presence of linear contaminants. Research into the synthesis of these polymers has made great progress in the past decade, and this review covers the synthesis, properties, and applications of cyclic polymers, with an emphasis on bio-based aliphatic polyesters. Synthetic routes to cyclic polymers synthesized from bioderived monomers, alongside mechanistic descriptions for both ring closure and ring expansion polymerization approaches, are reviewed. The review also highlights some of the unique physical properties of cyclic polymers together with potential applications. The findings illustrate the substantial recent developments made in the syntheses of cyclic polymers, as well as the progress which can be made in the commercialization of bio-based polymers through the versatility this topology provides.


Asunto(s)
Poliésteres , Polímeros , Polimerizacion
2.
Ann Intern Med ; 172(12): JC63, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32539520

RESUMEN

SOURCE CITATION: Cao B, Wang Y, Wen D, et al. A trial of lopinavir-ritonavir in adults hospitalized with severe Covid-19. N Engl J Med. 2020;382:1787-99. 32187464.


Asunto(s)
Neumonía Viral , Ritonavir , Adulto , Betacoronavirus , COVID-19 , Infecciones por Coronavirus , Humanos , Lopinavir , Pandemias , SARS-CoV-2
3.
Hepatol Res ; 49(3): 335-343, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30084205

RESUMEN

AIM: Prior randomized controlled trials of acute respiratory distress syndrome (ARDS) excluded critically ill patients with cirrhosis. Data regarding risk factors for ARDS development and outcomes from ARDS in patients with cirrhosis are scarce. We sought to characterize outcomes from ARDS in patients with cirrhosis. METHODS: An observational cohort of patients with cirrhosis admitted to an intensive care unit at a high-volume liver transplant center between 1 January 2012 and 31 December 2014 were reviewed. ARDS cases were identified according to the Berlin definition. Potential risk factors were examined in multivariable logistic regression analysis for ARDS development. Outcomes including in-hospital mortality were compared between ARDS and non-ARDS patients. RESULTS: A total of 559 patients met the inclusion criteria and 45 (8.1%) developed ARDS. Differences between ARDS and non-ARDS patients included sepsis, Model for End-Stage Liver Disease - Sodium score, and Sequential Organ Failure Assessment score. In-hospital mortality was higher in cirrhotic patients with ARDS compared with those without ARDS (82.2% vs. 27.6%, P < 0.001). In multivariable analysis, acute-on-chronic liver failure (OR 8.69, 95% CI 2.28-33.18, P < 0.01) and shock on intensive care unit admission (OR 3.13, 95% CI 1.57-6.24, P = 0.001) were associated with ARDS development, whereas etiology of cirrhosis or alcohol use were not. CONCLUSIONS: Acute-on-chronic liver failure and shock on intensive care unit admission were risk factors for ARDS development, whereas etiology of cirrhosis and alcohol were not. Mortality from ARDS was markedly increased in patients with cirrhosis. Early recognition and treatment for infection might be important for improving the high mortality in this group of patients.

6.
J Card Fail ; 21(7): 572-82, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25863169

RESUMEN

BACKGROUND: Although stem cell therapy (SCT) is emerging as a potential treatment for patients with dilated cardiomyopathy (DCM), clinical response remains variable. Our objective was to determine whether baseline differences in circulating immunologic and nonimmunologic biomarkers may help to identify patients more likely to respond to intramyocardial injection of CD34(+)-based SCT. METHODS AND RESULTS: We enrolled from January 3, 2011 to March 5, 2012 37 patients with longstanding DCM (left ventricular ejection fraction [LVEF] <40%, New York Heart Association functional class III) who underwent peripheral CD34(+) stem cell mobilization with granulocyte colony-stimulating factor (G-CSF) and collection by means of apheresis. CD34(+) cells were labeled with (99m)Tc-hexamethylpropyleneamine oxime to allow assessment of stem cell retention at 18 hours. Response to SCT was predefined as an increase in LVEF of ≥5% at 3 months. The majority (84%) of patients were male with an overall mean LVEF of 27 ± 7% and a median N-terminal pro-B-type natriuretic peptide (NT-proBNP) level of 2,774 pg/mL. Nineteen patients (51%) were responders to SCT. There was no significant difference between responders and nonresponders regarding to age, sex, baseline LVEF, NT-proBNP levels, or 6-minute walking distance. With the use of a partial least squares (PLS) predictive model, we identified 9 baseline factors that were associated with both stem cell response and stem cell retention (mechanistic validation). Among the baseline factors positively associated with both clinical response and stem cell retention were G-CSF, SDF-1, LIF, MCP-1, and MCP-3. Among baseline factors negatively associated with both clinical response and retention were IL-12p70, FASL, ICAM-1, and GGT. A decrease in G-CSF at 3-month follow-up was also observed in responders compared with nonresponders (P = .02). CONCLUSIONS: If further validated, baseline immunologic and nonimmunologic biomarkers may help to identify patients with DCM who are more likely to respond to CD34(+)-based SCT.


Asunto(s)
Cardiomiopatía Dilatada , Quimiocina CXCL12/sangre , Factor Estimulante de Colonias de Granulocitos , Molécula 1 de Adhesión Intercelular/sangre , Factor Inhibidor de Leucemia/sangre , Trasplante de Células Madre de Sangre Periférica/métodos , Adulto , Antígenos CD34/inmunología , Biomarcadores/sangre , Cardiomiopatía Dilatada/diagnóstico , Cardiomiopatía Dilatada/inmunología , Cardiomiopatía Dilatada/fisiopatología , Cardiomiopatía Dilatada/terapia , Femenino , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/inmunología , Movilización de Célula Madre Hematopoyética/métodos , Humanos , Masculino , Persona de Mediana Edad , Monitorización Inmunológica/métodos , Imagen de Perfusión Miocárdica/métodos , Radiofármacos/farmacología , Volumen Sistólico , Exametazima de Tecnecio Tc 99m/farmacología
7.
Crit Care Clin ; 40(2): 309-327, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38432698

RESUMEN

Acute respiratory distress syndrome (ARDS) is an acute inflammatory lung injury characterized by severe hypoxemic respiratory failure, bilateral opacities on chest imaging, and low lung compliance. ARDS is a heterogeneous syndrome that is the common end point of a wide variety of predisposing conditions, with complex pathophysiology and underlying mechanisms. Routine management of ARDS is centered on lung-protective ventilation strategies such as low tidal volume ventilation and targeting low airway pressures to avoid exacerbation of lung injury, as well as a conservative fluid management strategy.


Asunto(s)
Lesión Pulmonar , Síndrome de Dificultad Respiratoria , Humanos , Síndrome de Dificultad Respiratoria/diagnóstico , Síndrome de Dificultad Respiratoria/terapia , Rendimiento Pulmonar , Respiración Artificial
8.
Crit Care Explor ; 6(3): e1059, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38975567

RESUMEN

OBJECTIVES: To develop and validate machine learning (ML) models to predict high-flow nasal cannula (HFNC) failure in COVID-19, compare their performance to the respiratory rate-oxygenation (ROX) index, and evaluate model accuracy by self-reported race. DESIGN: Retrospective cohort study. SETTING: Four Emory University Hospitals in Atlanta, GA. PATIENTS: Adult patients hospitalized with COVID-19 between March 2020 and April 2022 who received HFNC therapy within 24 hours of ICU admission were included. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Four types of supervised ML models were developed for predicting HFNC failure (defined as intubation or death within 7 d of HFNC initiation), using routine clinical variables from the first 24 hours of ICU admission. Models were trained on the first 60% (n = 594) of admissions and validated on the latter 40% (n = 390) of admissions to simulate prospective implementation. Among 984 patients included, 317 patients (32.2%) developed HFNC failure. eXtreme Gradient Boosting (XGB) model had the highest area under the receiver-operator characteristic curve (AUROC) for predicting HFNC failure (0.707), and was the only model with significantly better performance than the ROX index (AUROC 0.616). XGB model had significantly worse performance in Black patients compared with White patients (AUROC 0.663 vs. 0.808, p = 0.02). Racial differences in the XGB model were reduced and no longer statistically significant when restricted to patients with nonmissing arterial blood gas data, and when XGB model was developed to predict mortality (rather than the composite outcome of failure, which could be influenced by biased clinical decisions for intubation). CONCLUSIONS: Our XGB model had better discrimination for predicting HFNC failure in COVID-19 than the ROX index, but had racial differences in accuracy of predictions. Further studies are needed to understand and mitigate potential sources of biases in clinical ML models and to improve their equitability.


Asunto(s)
COVID-19 , Cánula , Humanos , COVID-19/terapia , COVID-19/etnología , Masculino , Estudios Retrospectivos , Femenino , Persona de Mediana Edad , Anciano , Terapia por Inhalación de Oxígeno/métodos , Insuficiencia del Tratamiento , Aprendizaje Automático , SARS-CoV-2 , Unidades de Cuidados Intensivos , Ventilación no Invasiva/métodos
9.
Crit Care Explor ; 6(6): e1102, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38842419

RESUMEN

BACKGROUND: Tracheostomy-related acquired pressure injuries (TRPIs) are one of the hospital-acquired conditions. We hypothesize that an uneven ventilator circuit load, leading to non-neutral tracheostomy tube positioning in the immediate post-tracheostomy period, leads to an increased incidence of TRPIs. Does switching the ventilator circuit load daily, in addition to standard post-tracheostomy care, lead to a decreased incidence of TRPIs? METHODS: This is a prospective quality improvement study. Study was conducted at two academic hospital sites within tertiary care hospitals at Emory University in different ICUs. Consecutive patients undergoing bedside percutaneous tracheostomy by the interventional pulmonary service were included. The flip the ventilator circuit (FLIC) protocol was designed and implemented in selected ICUs, with other ICUs as controls. RESULTS: Incidence of TRPI in intervention and control group were recorded at post-tracheostomy day 5. A total of 99 patients were included from October 22, 2019, to May 22, 2020. Overall, the total incidence of any TRPI was 23% at post-tracheostomy day 5. Incidence of stage I, stage II, and stages III-IV TRPIs at postoperative day 5 was 11%, 12%, and 0%, respectively. There was a decrease in the rate of skin breakdown in patients following the FLIC protocol when compared with standard of care (13% vs. 36%; p = 0.01). In a multivariable analysis, interventional group had decreased odds of developing TRPI (odds ratio, 0.32; 95% CI, 0.11-0.92; p = 0.03) after adjusting for age, albumin, body mass index, diabetes mellitus, and days in hospital before tracheostomy. CONCLUSIONS: The incidence of TRPIs within the first week following percutaneous tracheostomy is high. Switching the side of the ventilator circuit to evenly distribute load, in addition to standard bundled tracheostomy care, may decrease the overall incidence of TRPIs.


Asunto(s)
Úlcera por Presión , Traqueostomía , Humanos , Traqueostomía/efectos adversos , Traqueostomía/métodos , Traqueostomía/instrumentación , Masculino , Femenino , Estudios Prospectivos , Persona de Mediana Edad , Anciano , Úlcera por Presión/prevención & control , Úlcera por Presión/etiología , Úlcera por Presión/epidemiología , Incidencia , Respiración Artificial/efectos adversos , Mejoramiento de la Calidad , Unidades de Cuidados Intensivos , Ventiladores Mecánicos/efectos adversos
10.
Res Sq ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38746442

RESUMEN

Background: Septic patients who develop acute respiratory failure (ARF) requiring mechanical ventilation represent a heterogenous subgroup of critically ill patients with widely variable clinical characteristics. Identifying distinct phenotypes of these patients may reveal insights about the broader heterogeneity in the clinical course of sepsis. We aimed to derive novel phenotypes of sepsis-induced ARF using observational clinical data and investigate their generalizability across multi-ICU specialties, considering multi-organ dynamics. Methods: We performed a multi-center retrospective study of ICU patients with sepsis who required mechanical ventilation for ≥24 hours. Data from two different high-volume academic hospital systems were used as a derivation set with N=3,225 medical ICU (MICU) patients and a validation set with N=848 MICU patients. For the multi-ICU validation, we utilized retrospective data from two surgical ICUs at the same hospitals (N=1,577). Clinical data from 24 hours preceding intubation was used to derive distinct phenotypes using an explainable machine learning-based clustering model interpreted by clinical experts. Results: Four distinct ARF phenotypes were identified: A (severe multi-organ dysfunction (MOD) with a high likelihood of kidney injury and heart failure), B (severe hypoxemic respiratory failure [median P/F=123]), C (mild hypoxia [median P/F=240]), and D (severe MOD with a high likelihood of hepatic injury, coagulopathy, and lactic acidosis). Patients in each phenotype showed differences in clinical course and mortality rates despite similarities in demographics and admission co-morbidities. The phenotypes were reproduced in external validation utilizing an external MICU from second hospital and SICUs from both centers. Kaplan-Meier analysis showed significant difference in 28-day mortality across the phenotypes (p<0.01) and consistent across both centers. The phenotypes demonstrated differences in treatment effects associated with high positive end-expiratory pressure (PEEP) strategy. Conclusion: The phenotypes demonstrated unique patterns of organ injury and differences in clinical outcomes, which may help inform future research and clinical trial design for tailored management strategies.

11.
PeerJ ; 12: e16738, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38390391

RESUMEN

The existence of coastal ecosystems depends on their ability to gain sediment and keep pace with sea level rise. Similar to other coastal areas, Northeast Florida (United States) is experiencing rapid population growth, climate change, and shifting wetland communities. Rising seas and more severe storms, coupled with the intensification of human activities, can modify the biophysical environment, thereby increasing coastal exposure to storm-induced erosion and inundation. Using the Guana Tolomato Matanzas National Estuarine Research Reserve as a case study, we analyzed the distribution of coastal protection services-expressly, wave attenuation and sediment control-provided by estuarine habitats inside a dynamic Intracoastal waterway. We explored six coastal variables that contribute to coastal flooding and erosion-(a) relief, (b) geomorphology, (c) estuarine habitats, (d) wind exposure, (e) boat wake energy, and (f) storm surge potential-to assess physical exposure to coastal hazards. The highest levels of coastal exposure were found in the north and south sections of the Reserve (9% and 14%, respectively) compared to only 4% in the central, with exposure in the south driven by low wetland elevation, high surge potential, and shorelines composed of less stable sandy and muddy substrate. The most vulnerable areas of the central Reserve and main channel of the Intracoastal waterway were exposed to boat wakes from larger vessels frequently traveling at medium speeds (10-20 knots) and had shoreline segments oriented towards the prevailing winds (north-northeast). To guide management for the recently expanded Reserve into vulnerable areas near the City of Saint Augustine, we evaluated six sites of concern where the current distribution of estuarine habitats (mangroves, salt marshes, and oyster beds) likely play the greatest role in natural protection. Spatially explicit outputs also identified potential elevation maintenance strategies such as living shorelines, landform modification, and mangrove establishment for providing coastal risk-reduction and other ecosystem-service co-benefits. Salt marshes and mangroves in two sites of the central section (N-312 and S-312) were found to protect more than a one-quarter of their cross-shore length (27% and 73%, respectively) from transitioning to the highest exposure category. Proposed interventions for mangrove establishment and living shorelines could help maintain elevation in these sites of concern. This work sets the stage for additional research, education, and outreach about where mangroves, salt marshes, and oyster beds are most likely to reduce risk to wetland communities in the region.


Asunto(s)
Ecosistema , Humedales , Humanos , Elevación del Nivel del Mar , Cambio Climático , Florida
12.
Crit Care Explor ; 5(6): e0930, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37346229

RESUMEN

To analyze the temporal trend in enrollment rates in a COVID-19 platform trial during the first three waves of the pandemic in the United States. DESIGN: Secondary analysis of data from the I-SPY COVID randomized controlled trial (RCT). SETTING: Thirty-one hospitals throughout the United States. PATIENTS: Patients who were approached, either directly or via a legally authorized representative, for consent and enrollment into the I-SPY COVID RCT. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among 1,338 patients approached for the I-SPY COVID trial from July 30, 2020, to February 17, 2022, the number of patients who enrolled (n = 1,063) versus declined participation (n = 275) was used to calculate monthly enrollment rates. Overall, demographic and baseline clinical characteristics were similar between those who enrolled versus declined. Enrollment rates fluctuated over the course of the COVID-19 pandemic, but there were no significant trends over time (Mann-Kendall test, p = 0.21). Enrollment rates were also comparable between vaccinated and unvaccinated patients. In multivariable logistic regression analysis, age, sex, region of residence, COVID-19 severity of illness, and vaccination status were not significantly associated with the decision to decline consent. CONCLUSIONS: In this secondary analysis of the I-SPY COVID clinical trial, there was no significant association between the enrollment rate and time period or vaccination status among all eligible patients approached for clinical trial participation. Additional studies are needed to better understand whether the COVID-19 pandemic has altered clinical trial participation and to develop strategies for encouraging participation in future COVID-19 and critical care clinical trials.

13.
Physiol Meas ; 44(10)2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37652033

RESUMEN

Objective. To examine whether heart rate interval based rapid alert (HIRA) score derived from a combination model of heart rate variability (HRV) and modified early warning score (MEWS) is a surrogate for the detection of acute respiratory failure (ARF) in critically ill sepsis patients.Approach. Retrospective HRV analysis of sepsis patients admitted to Emory healthcare intensive care unit (ICU) was performed between sepsis-related ARF and sepsis controls without ARF. HRV measures such as time domain, frequency domain, and nonlinear measures were analyzed up to 24 h after patient admission, 1 h before the onset of ARF, and a random event time in the sepsis controls. Statistical significance was computed by the Wilcoxon Rank Sum test. Machine learning algorithms such as eXtreme Gradient Boosting and logistic regression were developed to validate the HIRA score model. The performance of HIRA and early warning score models were evaluated using the area under the receiver operating characteristic (AUROC).Main Results. A total of 89 (ICU) patients with sepsis were included in this retrospective cohort study, of whom 31 (34%) developed sepsis-related ARF and 58 (65%) were sepsis controls without ARF. Time-domain HRV for Electrocardiogram (ECG) Beat-to-Beat RR intervals strongly distinguished ARF patients from controls. HRV measures for nonlinear and frequency domains were significantly altered (p< 0.05) among ARF compared to controls. The HIRA score AUC: 0.93; 95% confidence interval (CI): 0.88-0.98) showed a higher predictive ability to detect ARF when compared to MEWS (AUC: 0.71; 95% CI: 0.50-0.90).Significance. HRV was significantly impaired across patients who developed ARF when compared to controls. The HIRA score uses non-invasively derived HRV and may be used to inform diagnostic and therapeutic decisions regarding the severity of sepsis and earlier identification of the need for mechanical ventilation.


Asunto(s)
Insuficiencia Respiratoria , Sepsis , Humanos , Estudios Retrospectivos , Frecuencia Cardíaca/fisiología , Sepsis/complicaciones , Sepsis/diagnóstico , Unidades de Cuidados Intensivos , Curva ROC , Insuficiencia Respiratoria/complicaciones , Insuficiencia Respiratoria/diagnóstico , Factores de Transcripción , Proteínas de Ciclo Celular , Chaperonas de Histonas
14.
Int Immunopharmacol ; 124(Pt B): 110966, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37804660

RESUMEN

The global prevalence of Post-Acute Sequelae of SARS-CoV-2 Infection (PASC) stands at approximately 43 % among individuals who have previously had acute COVID-19. In contrast, in the United States, the National Center for Health Statistics (NCHS) estimates that around 11 % of individuals who have been infected with SARS-CoV-2 go on to experience long COVID. The underlying causes of PASC remains under investigation, and there are no currently established FDA-approved therapies. One of the leading hypotheses for the cause of PASC is the persistent activation of innate immune cells with increase systemic inflammation. Naltrexone is a medication with anti-inflammatory and immunomodulatory properties that has been used in other conditions that overlap with PASC. We performed a retrospective review of a clinical cohort of 59 patients at a single academic center who received low-dose naltrexone (LDN) off-label as a potential therapeutic intervention for PASC. The use of LDN was associated with a fewer number of symptoms, improved clinical symptoms (fatigue, post-exertional malaise, unrefreshing sleep, and abnormal sleep pattern), and a better functional status. This observation warrants testing in rigorous, randomized, placebo-controlled clinical trials.


Asunto(s)
COVID-19 , Humanos , Síndrome Post Agudo de COVID-19 , Naltrexona/uso terapéutico , SARS-CoV-2 , Progresión de la Enfermedad
15.
Crit Care Explor ; 4(10): e0780, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36284549

RESUMEN

The role of early, serial measurements of protein biomarkers in sepsis-induced acute respiratory distress syndrome (ARDS) is not clear. OBJECTIVES: To determine the differences in soluble receptor for advanced glycation end-products (sRAGEs), angiopoietin-2, and surfactant protein-D (SP-D) levels and their changes over time between sepsis patients with and without ARDS. DESIGN SETTING AND PARTICIPANTS: Prospective observational cohort study of adult patients admitted to the medical ICU at Grady Memorial Hospital within 72 hours of sepsis diagnosis. MAIN OUTCOMES AND MEASURES: Plasma sRAGE, angiopoietin-2, and SP-D levels were measured for 3 consecutive days after enrollment. The primary outcome was ARDS development, and the secondary outcome of 28-day mortality. The biomarker levels and their changes over time were compared between ARDS and non-ARDS patients and between nonsurvivors and survivors. RESULTS: We enrolled 111 patients, and 21 patients (18.9%) developed ARDS. The three biomarker levels were not significantly different between ARDS and non-ARDS patients on all 3 days of measurement. Nonsurvivors had higher levels of all three biomarkers than did survivors on multiple days. The changes of the biomarker levels over time were not different between the outcome groups. Logistic regression analyses showed association between day 1 SP-D level and mortality (odds ratio, 1.52; 95% CI, 1.03-2.24; p = 0.03), and generalized estimating equation analyses showed association between angiopoietin-2 levels and mortality (estimate 0.0002; se 0.0001; p = 0.04). CONCLUSIONS AND RELEVANCE: Among critically ill patients with sepsis, sRAGE, angiopoietin-2, and SP-D levels were not significantly different between ARDS and non-ARDS patients but were higher in nonsurvivors compared with survivors. The trend toward higher levels of sRAGE and SP-D, but not of angiopoietin-2, in ARDS patients may indicate the importance of epithelial injury in sepsis-induced ARDS. Changes of the biomarker levels over time were not different between the outcome groups.

16.
Macromolecules ; 55(24): 11051-11058, 2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36590371

RESUMEN

Small-angle neutron scattering (SANS) experiments were conducted on cyclic and linear polymers of racemic and l-lactides (PLA) with the goal of comparing chain configurations, scaling, and effective polymer-solvent interactions of the two topologies in acetone-d 6 and THF-d 8. There are limited reports of SANS results on cyclic polymers due to the lack of substantial development in the field until recently. Now that pure, well-defined cyclic polymers are accessible, unanswered questions about their rheology and physical conformations can be better investigated. Previously reported SANS experiments have used cyclic and linear polystyrene samples; therefore, our work allowed for direct comparison using a contrasting (structurally and sterically) polymer. We compared SANS results of cyclic and linear PLA samples with various microstructures and molecular weights at two different temperatures, allowing for comparison with a wide range of variables. The results followed the trends of previous experiments, but much greater differences in the effective polymer-solvent interaction parameters between cyclic and linear forms of PLA were observed, implying that the small form factor and hydrogen bonding in PLA allowed for much more compact conformations in the cyclic form only. Also, the polymer microstructure was found to influence polymer-solvent interaction parameters substantially. These results illustrate how the difference in polymer-solvent interactions between cyclic and linear polymers can vary greatly depending on the polymer in question and the potential of neutron scattering as a tool for identification and characterization of the cyclic topology.

17.
Artículo en Inglés | MEDLINE | ID: mdl-35010689

RESUMEN

The use of health insurance to cover legal abortion is a controversial issue on which Americans are sharply divided. Currently, there is a lack of research on this issue as data became available only recently. Using data from the newly released General Social Survey in 2018, this study examines who is more or less likely to support health insurance coverage for legal abortion. The results show that the support and opposition were about evenly divided. The findings from the logistic regression analysis reveal that, holding other variables constant, Democrats, liberals, urban residents, the more educated, and the older were more likely to support health insurance coverage for legal abortion while women, Southerners, Christians, the currently married, and those with more children were less likely to favor it, compared to their respective counterparts. Additionally, the effect of education was stronger for liberals than for non-liberals. Race, family income, and full-time work status make no difference in the outcome. The findings have significant implications for research and practices in health insurance coverage for legal abortion.


Asunto(s)
Aborto Legal , Seguro de Salud , Niño , Femenino , Humanos , Cobertura del Seguro , Embarazo , Estados Unidos
18.
Adv Sci (Weinh) ; 8(11): e2003987, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34105284

RESUMEN

Early measurements of tissue viability after myocardial infarction (MI) are essential for accurate diagnosis and treatment planning but are challenging to obtain. Here, manganese, a calcium analogue and clinically approved magnetic resonance imaging (MRI) contrast agent, is used as an imaging biomarker of myocardial viability in the first hours after experimental MI. Safe Mn2+ dosing is confirmed by measuring in vitro beating rates, calcium transients, and action potentials in cardiomyocytes, and in vivo heart rates and cardiac contractility in mice. Quantitative T1 mapping-manganese-enhanced MRI (MEMRI) reveals elevated and increasing Mn2+ uptake in viable myocardium remote from the infarct, suggesting MEMRI offers a quantitative biomarker of cardiac inotropy. MEMRI evaluation of infarct size at 1 h, 1 and 14 days after MI quantifies myocardial viability earlier than the current gold-standard technique, late-gadolinium-enhanced MRI. These data, coupled with the re-emergence of clinical Mn2+ -based contrast agents open the possibility of using MEMRI for direct evaluation of myocardial viability early after ischemic onset in patients.


Asunto(s)
Supervivencia Celular/efectos de los fármacos , Medios de Contraste/farmacología , Corazón/diagnóstico por imagen , Manganeso/farmacología , Infarto del Miocardio/diagnóstico , Animales , Gluconato de Calcio/farmacología , Modelos Animales de Enfermedad , Corazón/fisiopatología , Humanos , Imagen por Resonancia Magnética , Ratones , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/patología , Miocardio/patología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/patología
19.
PLoS One ; 16(9): e0257056, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34559819

RESUMEN

We present an interpretable machine learning algorithm called 'eARDS' for predicting ARDS in an ICU population comprising COVID-19 patients, up to 12-hours before satisfying the Berlin clinical criteria. The analysis was conducted on data collected from the Intensive care units (ICU) at Emory Healthcare, Atlanta, GA and University of Tennessee Health Science Center, Memphis, TN and the Cerner® Health Facts Deidentified Database, a multi-site COVID-19 EMR database. The participants in the analysis consisted of adults over 18 years of age. Clinical data from 35,804 patients who developed ARDS and controls were used to generate predictive models that identify risk for ARDS onset up to 12-hours before satisfying the Berlin criteria. We identified salient features from the electronic medical record that predicted respiratory failure among this population. The machine learning algorithm which provided the best performance exhibited AUROC of 0.89 (95% CI = 0.88-0.90), sensitivity of 0.77 (95% CI = 0.75-0.78), specificity 0.85 (95% CI = 085-0.86). Validation performance across two separate health systems (comprising 899 COVID-19 patients) exhibited AUROC of 0.82 (0.81-0.83) and 0.89 (0.87, 0.90). Important features for prediction of ARDS included minimum oxygen saturation (SpO2), standard deviation of the systolic blood pressure (SBP), O2 flow, and maximum respiratory rate over an observational window of 16-hours. Analyzing the performance of the model across various cohorts indicates that the model performed best among a younger age group (18-40) (AUROC = 0.93 [0.92-0.94]), compared to an older age group (80+) (AUROC = 0.81 [0.81-0.82]). The model performance was comparable on both male and female groups, but performed significantly better on the severe ARDS group compared to the mild and moderate groups. The eARDS system demonstrated robust performance for predicting COVID19 patients who developed ARDS at least 12-hours before the Berlin clinical criteria, across two independent health systems.


Asunto(s)
COVID-19 , Aprendizaje Automático , Modelos Biológicos , Síndrome de Dificultad Respiratoria , SARS-CoV-2/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/sangre , COVID-19/complicaciones , COVID-19/diagnóstico , COVID-19/fisiopatología , Enfermedad Crítica , Femenino , Humanos , Masculino , Sistemas de Registros Médicos Computarizados , Persona de Mediana Edad , Oxígeno/sangre , Síndrome de Dificultad Respiratoria/sangre , Síndrome de Dificultad Respiratoria/diagnóstico , Síndrome de Dificultad Respiratoria/etiología , Síndrome de Dificultad Respiratoria/fisiopatología , Frecuencia Respiratoria , Factores de Riesgo
20.
J Racial Ethn Health Disparities ; 7(3): 446-457, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31768963

RESUMEN

The present study intended to evaluate whether 4 discrete ethnic groups of Asian immigrants could, for empirical reasons, be assigned a set of unique operating factors explaining health outcomes of members. The set comprised several acculturation, social structure, lifestyle, and health-related factors. Our study asked if these factors uniformly explained health outcomes across the 4 groups. We pooled National Health Interview Survey (NHIS) data dating 1999-2015 and developed 2 outcomes: self-rated health and self-reported chronic illness (specifically, diagnosis of cardiovascular disease, prediabetes/diabetes, hypertension, cancer, or stroke). Since data for smaller Asian ethnic groups are not readily available, we confined our analyses to respondents of Chinese, Filipino, Asian Indian, and "other Asian" ethnicity. Descriptive statistics suggested that Asian Indian respondents were least likely to report having 1 of the 5 specified serious illnesses and self-rated their health higher than the other 3 respondent groups. Additionally, while some factors (e.g., body mass index, depression) proved related to the health outcomes across the 4 ethnic groups, we did observe for each group a unique pattern of factors associated with the outcomes. Our results confirmed, furthermore, a moderating role for ethnicity in associations between the outcomes and those operating factors in the set we evaluated. The study results should be of use in tailoring preventive and intervention programs to various ethnic groups of Asian immigrants; clearly, in promoting health, one approach will not fit all.


Asunto(s)
Asiático/estadística & datos numéricos , Enfermedad Crónica/epidemiología , Emigrantes e Inmigrantes/estadística & datos numéricos , Etnicidad/estadística & datos numéricos , Estado de Salud , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Pueblo Asiatico/estadística & datos numéricos , Enfermedad Crónica/etnología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estados Unidos/epidemiología , Estados Unidos/etnología , Adulto Joven
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